Apparatus and method for pre-condensing and pressing fiber material into a bale

ABSTRACT

A vertical fiber material collecting chute is arranged over a bale press to feed successive pre-condensed charges of fiber material into the press for pressing into a bale. An air pressure differential is maintained on each charge during formation in the chute by the transporting air stream in order to pre-condense. Upon depositing a charge into the press, the air stream is diverted towards the press in order to push the charge into the press as an aid to gravity.

United States Patent 1191 Nitschke July 22, 1975 [54] APPARATUS AND METHOD FOR 2,488,395 11/1949 Goldberg 100/91 PRE CONDENSING AND PRESSING FIBER 2,984,172 5/1961 Roberts et a1. 100/90 3,212,432 10/1965 Raab 100/90 X MATERIAL INTO A BALE 3,487,771 1/1970 Crane et a]. 100/215 x [75] Inventor: Heinz Nitschke, Winterthur, 3,513,771 5/1970 Felts 100/215 Switzerland 3,580,644 5/1971 Ballard 302/59 3,583,770 6/1971 Medhammar.... 100/229 A X Assignee: Rieter Machine s, -9 3,635,002 1/1972 Ries 100/229 A x Winterthur, Switzerland 3,721,060 3/1973 Quinto 100/220 X [22] Filed Nov 21 1973 3,788,368 1/1974 Geng 141/67 1' PP ,738 Primary Examiner-Billy J. Wilhite Attorney, Agent, or Firm-Kenyon & Kenyon, Reilly, 30 Foreign Application Priority Data P' Nov. 27, 1972 Switzerland 17218/72 [57] ABSTRACT [52] A vertical fiber material collecting chute is arranged loo/59 l4l/67. 302/59 over a bale press to feed successive pre-condensed I t Cl B30b 13/00 charges of fiber material into the press for pressing i loo/3 into a bale. An'air pressure differential is maintained {B 3 99 48 i on each charge during formation in the chute by the 6 ,3 transporting air stream in order to pre-condense. Upon depositing a charge into the press, the air stream References Cited is diverted towards the press in order to push the UNITED STATES PATENTS 12/1934 Bethe] 100/220 charge into the press as an aid to gravity.

13 Claims, 13 Drawing Figures PATENTEnJuLzz 1915 3,895,572

SHEET 1 APPARATUS AND METHOD FOR PRE-CONDENSING AND PRESSING FIBER MATERIAL INTO A BALE This invention relates to an apparatus and method for pre-condensing and pressing fiber material into a bale.

Heretofore, various types of equipment have been known in which fiber material is transferred via an air stream into a press box provided with openings for draining off the air. Generally, the press box is vertical and is enclosed by envelope walls which are arranged at a certain axial distance from the press box and which are connected with a suction fan in such a manner that a vacuum prevails in the press box in order to effect a precondensation of the fiber material in the press box depending on the vacuum. In operation, the fiber material has been brought into the vertically arranged press box in loose form and pressed by several pressing cycles of a movable press rod, i.e. layer by layer, into a complete bale. Subsequently, doors provided in the press box and in the surrounding envelope walls are opened, the bale tied and thereafter withdrawn from the press box.

In some cases, the suction fan is connected on the pressure side to a filter hose arrangement above the press so that the fiber parts sucked off via the openings of the press box can be separated from the air drained off via the filter hose.

The disadvantages of such equipment reside in that the press box is also used as the fiber collecting box for taking up the loose fiber material which is not yet precondensed. As a result, a correspondingly long press box is required along with a correspondingly long lift for the pressrod and piston used to press the fiber material. This all leads to a very high construction height. A further disadvantage resides in that a filter installation is required downstream of the evacuated press box which requires perforated wall plates to prevent the loss of fiber particles escaping via the openings in the press box or the blowing out of such filter particles into the surrounding atmosphere.

Accordingly, it is an object of the invention to be able to pre-condense successive charges of fiber material prior to forming a bale from the charges within a minimum of space.

It is another object of the invention to provide a bale forming apparatus of minimum height.

It is another object of the invention to avoid the need for air filters downstream of an evacuated press box of bale forming apparatus.

It is another object of the invention to use a fiber collecting chute as an air filter.

Briefly, the invention provides an apparatus and method in which successive charges of fiber material are formed and pre-condensed in a vertical collecting chute and thereafter deposited into a bale press below the chute for pressing into a bale. The fiber collecting chute is constructed with an inner envelope to define a first chamber to receive a fiber material laden transporting air stream. The inner envelope is made air permeable to retain the fiber material while allowing the transporting air to drain off. In addition, the chute has an outer envelope which substantially encloses the inner envelope to form a second chamber. The outer envelope has an air exit opening through which the air passed from the first chamber into the second chamber can be exhausted.

In order to control the discharge of fiber material, a means such as a movable slide plate is disposed at the exit of the fiber collecting chute into the bale press. This plate serves to seal the chute in an airtight manner from the press in which atmospheric pressure prevails during precon'densing of the charge in the chute. In addition, means are provided for detecting the fiber level in the chute. This means is connected to a control means for activating the sliding plate in order to move the plate out of the path of the charge in the chute so that the charge can drop under gravity into the bale press. An additional means is also provided for increasing the air pressure in the chute when a predetermined height or fiber deposit level is reached. This means is also connected to the control means to be activated thereby when the chute is opened in order to impose an additional force on the charge to push the charge into the bale press.

The method resides in the steps of pre-condensing the fiber material in the fiber collecting chute to a presetable degree by the use of an air pressure differential on the charge from the chute inlet to the surrounding chamber about the inner envelope prior to discharge into the bale press. In addition, the method uses the steps of lowering the precondensed fiber material into the bale press with the assistance of an air pressure drop generated between the chute and the press and of lowering the fiber material as a function of a preselectable fiber deposit height level in the chute. The control means used can also be provided for influencing the means used to feed the fiber collecting chute with fiber material.

These and other objects and advantages of the invention will become more apparent from the following detailed description and appended claims taken in conjunction with the accompanying drawings in which:

FIG. 1 illustrates a schematic longitudinal sectional view of a press with a fiber collecting chute according to the invention;

FIG. 2 illustrates a top view of the fiber collecting chute taken along line I of FIG. 1;

FIG. 3 illustrates a partial top view of the bale press of FIG. 1 with a formed bale therein; and

FIG. 4 illustrates a view similar to FIG. 3 with the bale press opened for the removal of a bale.

Referring to FIG. 1, a vertical fiber collecting chute l is arranged in correspondence with a horizontal fiber bale press 2. The fiber collecting chute I has an inner envelope consisting substantially of a cylindrical filter hose 3 clamped onto an entry member 4 by a coupling strap 5 and clamped onto an exit member 6 by a coupling strap 7. The hose 3 defines an inner chamber 28 for retaining fiber material from the air stream and extends loosely between the ends. The entry member 4 is provided with an entry tube 8 for receiving a fiber laden air transporting stream and is rigidly connected with an outer envelope formed, e.g. by a cylindrical wall 9 or with an upper face plate 10. The exit member 6 is rigidly connected with the outer envelope 9 via a flange 11 and the lower end is arranged flush with a press entry member 12 of the fiber bale press 2. The outer envelope 9 is provided with an air exit tube 13 for exhausting air passed out of the hose 3 from the fiber collecting chamber.

A means for sealing the tube 13 is provided which consists of a rotatable sealing baffle 14 in the tube 13. This baffle 14 is activated by a controlled compressed air cylinder which is pivotably connected with the outer envelope 9 via a support 16. The cylinder 15 is, in turn, connected over a solenoid valve 15a to the control means 23 for purposes as explained below.

The annularly shaped chamber 17 formed between the hose 3 and the outer envelope 9 has a fiber level detecting means located therein. This detecting means serves to detect a predetermined height of deposited charge in the chamber 28 formed by the hose 3 for purposes as explained below. The detecting means includes an ultrasonic emitter 18 arranged on one side of the filter hose 3 opposite to which an ultrasonic receiver 19 is arranged. Both the emitter l8 and receiver 19 together form an ultrasonic barrier 20. The emitter 18 and the receiver 19 are each mounted in a vertically adjustable manner on a support member 21 fixed on the outer envelope 9 as indicated by arrows 22 (FIG. 1) so as to be set for different fiber charge heights. Each of the emitter 18 and the receiver 19 is also connected with the control means 23 in order to emit a signal thereto in response to the fiber material attaining the level programmed for the detecting means 18, 19. A control switch 24 is also provided in a line between the receiver 19 and the control means 23 for presetting the switching point of the receiver 19.

In order to monitor the pressure differential on the column of fiber material inside the hose 3, a controllable pressure differential gauge switch 25 is connected on one side via a pressure duct 26 and a filter 27 with the inside chamber 28 formed by the hose 3 and on another side via a pressure duct 29 and a filter 30 with the intermediate chamber 17. The pressure differential gauge switch 25 is also connected with the control unit 23 in order to deliver a signal thereto corresponding to the differential in pressure between the chute inlet or inner chamber 28, and the intermediate chamber 17 for purposes as explained below.

A means is provided between the lower end of the chute 1 and the bale press 2 in order to selectively seal the chute 1 from the press 2. This means includes a sliding plate 32, or other suitable device, which is activated by a cylinder 31 to close the lower end of the inner chamber 28. The cylinder 31 is connected to the control means 23 via a solenoid valve 31a for purposes as explained below.

The bale press 2 defines a horizontal pressing space 34 to receive the fiber material discharged from the chute l and includes a suitable means for pressing successively received charges into a fiber bale. This means includes a cylinder 33 which activates a press stamp 35 which is movably mounted in the press space 34 in order to press the fiber material together. The cylinder 33 is connected to the control means 23 via a solenoid valve 33a. In addition, a capacitive gauge 36 is disposed adjacent to and flush with the press space 34 to indicate the filling level of the space 34. The gauge 36 is connected over a suitable line to the control means 23 to delivera signal thereto for purposes as described below. The bale press 2 also includes a door 38 at the exit end which is movable under the influence of a cylinder 37 to open and close the space 34 to the exterior surroundings. The cylinder 37 is activated via a solenoid valve 37a as explained below.

A bale tieing space or room 39 is located within the bale press 2 in order to tie up a compressed bale ejected from the press space 34. To this end, as shown in FIGS. 3 and 4, a pair of arms 40 are linked to bolts 41 anchored in one side of the press 2 and a pair of arms 42 are hinged to the free ends of the arms 40 for pivoting in the bale take-off direction A. A pair of arms 43 are also linked to bolts 44 in the opposite side of the press 2.

The arms 43 are provided with locking claws 45 and the arms 43 are provided with locking claws 46, which claws 45, 46 serve as a means to lock the three arms 40, 42 and 43 into a closed frame each. These frames are capable of taking up the pressures actingin the directions A and B created when a pressed fiber bale 47 is moved out of the space 34 into the space 39. Each of the arms 46, 43 are each provided with a cylinder 48, the piston 49 of which, in an outer position (FIG. 3), reaches into the side zone of a bale 47 moved into the space 39 immediately adjacent to the stamp 35. The cylinders 48 are connected with the control means 23 via a solenoid valve 48a. The pistons 49 and valves 48a act as a holding means for holding a bale in the space 39.

In order to supply fiber material, a fan 50 is provided upstream of the chute 1 to generate a transporting air stream into which fiber material is passed. This fan 50 is connected to the control means 23 via a connection for purposes as explained below.

In operation, in an initial phase (FIG. 1), the baffle 14 is open, the sliding plate 32 is closed, the press stamp 35 is in a starting position, the door 38 is closed, the bale tieing space 39 is locked and the pistons 49 are in starting position (FIG. 4). The control unit 23 is then switched on by activating a switch 51. The fan 50 is thus activated to transport a mixture of air and fibers, fed on the suction side into a funnel 52, into the fiber collecting chamber 28 of the chute l. The fiber material then deposits in the chamber 28 while the air passes out of the hose 3. The pressure differential generated by the air flow resistance of the filter hose 3 and of the fiber material collected in the collecting space 28 then serves to pneumatically pre-condense the fiber material in the chamber 28. As the material deposited reaches the level C of the ultrasonic barrier 20, the control means 23 receives a signal from the ultrasonic receiver 9. The control means 23 then activates the solenoid valve 31a and thus the cylinder 31 which, in turn, opens the sliding plate 32. The control means 23 also activates the solenoid valve 15a and thus the cylinder 15 which, in turn, closes the baffle 14. Thus, the fiber material under the influence of gravity drops into the press space 34. The pressure drop with respect to the press space 34 generated by the fan 50 and increased as the baffle I4 is closed assists this dropping of the material in the sense of an acceleration. The air entering the press space 34 together with the fiber material escapes via small openings (FIG. ll) provided in the press space 34 into the surrounding room.

After a time delay, preset by an adjustable timing relay of the control means 23, the baffle 14 is reopened and the sliding plate 32 is closed again. The opening of the slide plate 32 and the closing of the baffie 14 can be effected simultaneously or staggered by a certain time interval. The time interval pre-set for dropping the material is chosen sufficiently short in order to avoid accumulations of fibers in the transporting duct between the fan 50 and the fiber collecting chute I which could result in clogging of the duct. Subsequently, the press stamp 35 is activated by the control means 23 via the solenoid valve 33a and the cylinder 33 and presses the fiber material into a part-layer. A plurality of such part-layers form a bale 47. The gauge 36, indicating the filling level, transmits a signal to the control means 23 as the desired bale size is reached. Thereupon, the door 38 is opened by means of the cylinder 37 and the press stamp 35 moves the bale into the bale tieing space 39 (FIG. 3); the lift of the press stamp 35 being limited by a stop (not shown). The press stamp 35 remains in this end position until the bale is fixed in the space 39 by the action of the pistons 49.

Subsequently, the stamp 35 is again retracted into the starting position and the door 38 is closed. The control means 23, upon receiving the signal from the gauge 36 indicating the filling level, simultaneously activates an acoustical signal device 53 emitting an intermitting signal. The attention of the personnel is thus attracted to the completed bale 47 which is moved out of the press. The bale is subsequently tied by the personnel. The personnel answers the call by pushing a switch 54 which deactivates an electric interlock in the control means 23 activated by the gauge 36 in order to prevent a further bale expulsion cycle.

If the interlock is not deactivated, the sliding plate 32 remains closed even if the fiber deposit level C is reached. The additionally deposited fiber material then causes the charge to reach a height level in the filter hose 3 at which the air permeable filter surface is reduced to such an extent that the pressure drop and thus, the air pressure in the chamber 28, exceeds a value preset in the pressure differential gauge switch 25. Thus, the control means 23 replaces the intermitting acoustical signal by a continuous one, and a presettable timing relay (not shown) is activated which, after the lapse of the preset time interval, switches off the fan 50 and, thus, stops the supply of fiber material into the fiber collecting chute 1. in this manner, no over-filling of the fiber collecting chute 1 can occur.

Among the particular advantages of the invention is the use of the fiber collecting chute as an air filter in addition to the normal use as a collecting means. Further, the vertical arrangement of the fiber collecting chute and the corresponding horizontal arrangement of the press permits an advantageous construction of a size which can conveniently fit into normal room heights. Still further, the generation of an increased air pressure permits fast and practically complete dropping or expelling of the precondensed fiber material from the fiber collecting chute.

Also, the inside wall of the filter hose is cleaned by the discharge of the precondensed fiber material over the filling height range. The use of a filter hose and the loose untensioned mounting as an inner envelope results in a movement, and thus cleaning, of the inner envelope under the influence of the transporting air stream.

The productivity of the press is increased insofar as a bale tieing space is provided which permits expulsion of the bale immediately upon completion of the pressing action. The press is thus ready to take up fiber material immediately thereafter.

What is claimed is:

1. Apparatus for pre-condensing by means of air pressure and pressing fiber material into a bale comprising a fiber collecting chute having an inner air permeable envelope defining a first chamber to receive a fiber laden air transporting stream, an outer envelope enclosing said inner envelope to define a second chamber and an air exit opening in said outer envelope for exhausting air passed from said first chamber into said secondchamber through saidinner envelope;

a bale press disposed vertically below said first chamber to receive fiber material therefrom;

a movable slide plate disposed between said collecting chute and said bale press for selectively sealing said bale press from said first chamber;

a first means for detecting a level of fiber in said first chamber of said collecting chute;

a second means for increasing the air pressure in said first chamber of said collecting chute; and

a control means for activating said slide plate to unseal said bale press from said first chamber and said second means to increase the air pressure in said first chamber above the received fiber material in response to the fiber material reaching a predetermined level in said first chamber.

2. Apparatus as set forth in claim 1 further comprising a third means for detecting an air pressure differential between said second chamber and said first chamber and for transmitting a signal in response to the differential exceeding a predetermined pressure differential.

3. Apparatus as set forth in claim 2 which further comprises means for feeding fiber material to said first chamber, said latter means being connected to said control means and said third means is connected to said control means to deactivate said latter means in response to said signal.

4. Apparatus as set forth in claim 2 wherein said third means is a presetable pressure differential gauge swtich.

5. Apparatus as set forth in claim 1 wherein said innner envelope is a filter hose having fixedly mounted ends.

6. Apparatus as set forth in claim 5 wherein said filter hose extends loosely between said ends for movement under a flow of air passing through said hose.

7. Apparatus as set forth in claim 1 further comprising a bale tieing room adjacent said bale press for taking up a bale upon completion of bale press action, said bale tieing room including movable and lockable arms for holding a compressed bale therebetween, said arms including means for holding a bale in said bale tieing room.

8. Apparatus as set forth in claim 7 wherein said means, for holding include cylinders each having a piston movable into said bale tieing room and solenoid valves for activating said cylinders.

9. Apparatus as set forth in claim 8 wherein said solenoid valves are connected to said control means for activation thereby.

10. A method for pre-condensing and pressing fiber material into a fiber bale comprising the steps of forming a charge of fiber material in a vertical collecting chute,

pre-condensing the charge in the chute to a presetable degree under an air pressure differential, and

depositing the pre-condensed charge into a bale press below the chute while subjecting the charge to an increased pressure differential between the chute and press, said step of depositing being carried out in response to a predetermined height of the charge in the chute.

11. A method as set forth in claim 10 which further includes the step of passing a fiber material laden air stream into the chute to deposit fiber material therein to form the charge while passing the air stream out of the chute to create said air pressure differential in the chute.

12. A method as set forth in claim 11 which further includes the step of passing the air stream from the chute into the bale press upon depositing of the charge into the bale press to create said increased pressure differential.

13. Apparatus for pneumatically pre-condensing and pressing fiber material into a bale comprising a fiber collecting chute having an air permeable envelope defining a chamber to receive a flow of fiber laden transporting air for formation and precondensing if a charge of fiber material in said chamber under a first air pressure differential,

a bale press below said chamber to receive the charge of fiber material from said chamber,

first means for selectively sealing said chamber from said bale press to prevent the charge of fiber material from passing into said bale press during precondensing,

means for activating said first means to open said chamber to said bale press to discharge the precondensed charge into said bale press for formation of a fiber bale therein; and

means for increasing said air pressure differential between said chute and said bale press with activation of said first means to accelerate to the discharge of the precondensed charge into said bale press. 

1. Apparatus for pre-condensing by means of air pressure and pressing fiber material into a bale comprising a fiber collecting chute having an inner air permeable envelope defining a first chamber to receive a fiber laden air transporting stream, an outer envelope enclosing said inner envelope to define a second chamber and an air exit opening in said outer envelope for exhausting air passed from said first chamber into said second chamber through said inner envelope; a bale press disposed vertically below said first chamber to receive fiber material therefrom; a movable slide plate disposed between said collecting chute and said bale press for selectively sealing said bale press from said first chamber; a first means for detecting a level of fiber in said first chamber of said collecting chute; a second means for increasing the air pressure in said first chamber of said collecting chute; and a control means for activating said slide plate to unseal said bale press from said first chamber and said second means to increase the air pressure in said first chamber above the received fiber material in response to the fiber material reaching a predetermined level in said first chamber.
 2. Apparatus as set forth in claim 1 further comprising a third means for detecting an air pressure differential between said second chamber and said first chamber and for transmitting a signal in response to the diffeRential exceeding a predetermined pressure differential.
 3. Apparatus as set forth in claim 2 which further comprises means for feeding fiber material to said first chamber, said latter means being connected to said control means and said third means is connected to said control means to deactivate said latter means in response to said signal.
 4. Apparatus as set forth in claim 2 wherein said third means is a presetable pressure differential gauge swtich.
 5. Apparatus as set forth in claim 1 wherein said innner envelope is a filter hose having fixedly mounted ends.
 6. Apparatus as set forth in claim 5 wherein said filter hose extends loosely between said ends for movement under a flow of air passing through said hose.
 7. Apparatus as set forth in claim 1 further comprising a bale tieing room adjacent said bale press for taking up a bale upon completion of bale press action, said bale tieing room including movable and lockable arms for holding a compressed bale therebetween, said arms including means for holding a bale in said bale tieing room.
 8. Apparatus as set forth in claim 7 wherein said means, for holding include cylinders each having a piston movable into said bale tieing room and solenoid valves for activating said cylinders.
 9. Apparatus as set forth in claim 8 wherein said solenoid valves are connected to said control means for activation thereby.
 10. A method for pre-condensing and pressing fiber material into a fiber bale comprising the steps of forming a charge of fiber material in a vertical collecting chute, pre-condensing the charge in the chute to a presetable degree under an air pressure differential, and depositing the pre-condensed charge into a bale press below the chute while subjecting the charge to an increased pressure differential between the chute and press, said step of depositing being carried out in response to a predetermined height of the charge in the chute.
 11. A method as set forth in claim 10 which further includes the step of passing a fiber material laden air stream into the chute to deposit fiber material therein to form the charge while passing the air stream out of the chute to create said air pressure differential in the chute.
 12. A method as set forth in claim 11 which further includes the step of passing the air stream from the chute into the bale press upon depositing of the charge into the bale press to create said increased pressure differential.
 13. Apparatus for pneumatically pre-condensing and pressing fiber material into a bale comprising a fiber collecting chute having an air permeable envelope defining a chamber to receive a flow of fiber laden transporting air for formation and pre-condensing if a charge of fiber material in said chamber under a first air pressure differential, a bale press below said chamber to receive the charge of fiber material from said chamber, first means for selectively sealing said chamber from said bale press to prevent the charge of fiber material from passing into said bale press during pre-condensing, means for activating said first means to open said chamber to said bale press to discharge the pre-condensed charge into said bale press for formation of a fiber bale therein; and means for increasing said air pressure differential between said chute and said bale press with activation of said first means to accelerate to the discharge of the precondensed charge into said bale press. 